Conventional command generators have been required to prevent excitation of high-frequency vibrations caused by an accelerated stage and reduce the setting time. To meet the requirements, there is a method including: dividing an acceleration & deceleration interval into three intervals of an acceleration increasing interval, a constant acceleration interval, and an acceleration decreasing interval; expressing position commands for the acceleration increasing interval and the acceleration decreasing interval as respective 7th-order functions; and determining each coefficient of the 7th-order functions so that the rate of change of acceleration (also referred to as jerk) varies continuously with time (Patent Literature 1).